The aim of this project is to transmit analog sound from a commercial mp3 player digitally using a store-bought laser pointer as the transmitter. This will be achieved mainly by performing analog-digital conversions, and by using a digitally phase-locked loop (DPLL) to synchronize the clock signals on both the transmitter and the receiver. This pr
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oject was carried out in Jan 2012 - April 2012 as a group of 5 team-mates. Since the beginning of civilization, man has sought to communicate with each other over long distances. From the primitive usage of smoke signals to groundbreaking technologies of their time such as the telegraph and telephone, communication technology has seen rapid improvement and development in recent years into today`s 3G/4G cellular data networks and fiber-optic internet linkage which are commonly used by people worldwide. The ability to convert analog signals to digital ones for transmission has revolutionized the communication industry. Out of the various types of analog-digital transmissions, the Pulse Code Modulation (PCM) scheme is one of the most common. Apart from its usage in audio recording and compression, the PCM scheme is also used in Public Switch-Telephone Networks (PSTNs), whose primary objective is to use a modulation scheme to convert analog human voice signals into digital signals for transmission, and also to be able to convert the digital signals back into the original analog signal after reception. In comparison with analog transmissions, digital data transmissions have the significant advantage that discrete and finite levels of digital signals have intervals which cause it to be less vulnerable to distortions caused by ambient noise, which in turn make recovering the signal much easier. One way of transmitting digital data...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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